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January 15, 2015

Infertility Treatments Do Not Appear to Contribute to Developmental Delays in Children

Children conceived via infertility treatments are no more likely to have a developmental delay than children conceived without such treatments, according to a study by researchers at NIH, the New York state department of health and other institutions. The findings, published online in JAMA Pediatrics, may help to allay longstanding concerns that conception after infertility treatment could affect the embryo at a sensitive stage and result in lifelong disability.

The authors found no differences in developmental assessment scores of more than 1,800 children born to women who became pregnant after receiving infertility treatment and those of more than 4,000 children born to women who did not undergo such treatment.

“When we began our study, there was little research on the potential effects of conception via fertility treatments on U.S. children,” said Dr. Edwina Yeung, a population health researcher at NICHD. “Our results provide reassurance to the thousands of couples who have relied on these treatments to establish their families.”

Also taking part in the study were researchers from the University at Albany, N.Y., and CapitalCare Pediatrics in Troy, N.Y. The Upstate KIDS study enrolled infants born to women in New York state (except for New York City) from 2008 to 2010. Parents of infants whose birth certificates indicated infertility treatment were invited to enroll their children in the study, as were all parents of twins and other multiples. The researchers also recruited roughly three times as many singletons not conceived via infertility treatment.

Four months after giving birth, the mothers indicated on a questionnaire the type of infertility treatment they received. Parents also completed a questionnaire to screen children for developmental disabilities at numerous intervals throughout their children’s first 3 years of life: at 4-6, 8, 12, 18, 24 and 36 months of age. The questionnaire covered five main developmental areas, or domains: fine motor skills, gross motor skills, communication, personal and social functioning and problem solving ability. Overall, children conceived via fertility treatments scored similarly to other children on the five areas covered in the developmental assessments.

Speeding Up Brain’s Waste Disposal May Slow Down Neurodegenerative Diseases

A study of mice shows how proteasomes, a cell’s waste disposal system, may break down during Alzheimer’s disease, creating a cycle in which increased levels of damaged proteins become toxic, clog proteasomes and kill neurons. The study, published in Nature Medicine and supported by NIH, suggests that enhancing proteasome activity with drugs during the early stages of Alzheimer’s may prevent dementia and reduce damage to the brain.

A graphic showing various parts of the brain in color

“This exciting research advances our understanding of the role of the proteasomes in neurodegeneration and provides a potential way to alleviate symptoms of neurodegenerative disorders,” said Dr. Roderick Corriveau, program director at NINDS, which provided funding for the study.

The proteasome is a hollow, cylindrical structure that chews up defective proteins into smaller pieces that can be recycled into new proteins needed by a cell. To understand how neurodegenerative disorders affect proteasomes, Dr. Natura Myeku, a postdoctoral fellow working with Dr. Karen E. Duff, professor of pathology and cell biology at Columbia University, focused on tau, a structural protein that accumulates into clumps called tangles in the brain cells of patients with Alzheimer’s disease and several other neurodegenerative disorders known as tauopathies.

Using a genetically engineered mouse model of tauopathy, as well as looking at cells in a dish, the scientists discovered that as levels of abnormal tau increased, the proteasome activity slowed down.

Scientists Manipulate Consciousness In Rats

Scientists showed that they could alter brain activity of rats and either wake them up or put them in an unconscious stateby changing the firing rates of neurons in the central thalamus, a region known to regulate arousal. The study, published in eLIFE, was partially funded by NIH.

“Our results suggest the central thalamus works like a radio dial that tunes the brain to different states of activity and arousal,” said Dr. Jin Hyung Lee, assistant professor of neurology, neurosurgery and bioengineering at Stanford University and a senior author of the study.

Located deep inside the brain, the thalamus acts as a relay station sending neural signals from the body to the cortex. Damage to neurons in the central part of the thalamus may lead to problems with sleep, attention and memory. Previous studies suggested that stimulation of thalamic neurons may awaken patients who have suffered a traumatic brain injury from minimally conscious states.

Lee’s team flashed laser pulses onto light sensitive central thalamic neurons of sleeping rats, which caused the cells to fire. High frequency stimulation of 40 or 100 pulses per second woke the rats. In contrast, low frequency stimulation of 10 pulses per second sent the rats into a state reminiscent of absence seizures that caused them to stiffen and stare before returning to sleep.

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